HDMI to SDI 4K miniconverter problems

I have 4 HDMI to SDI 4K MiniConverters connected to an ATEM 2 M/E Production Studio 4K. I have the switcher set to 1080i 59.94. I have tried 5 different devices (cameras and computers) with HDMI outputs and only 1 of them will work with the converters. There appears to be no SDI output from the converter to the switcher. All 5 devices work fine with the HDMI input on the ATEM switcher.
I have plugged the 5 devices to my monitor and the monitor displays that it is receiving a 1080i 60 Hz signal for all 5.
What could be the problem with using the converters?
Why would the HDMI signals work fine with the ATEM switcher HDMI input but not the converters?

There are 2 problems.

1. Your computers (and therefore the converters) are outputing 1920x1080 60hz and 59.94hz. The ATEM 4k series only accepts 59.94 via SDI, but will accept both 60 and 59.94 via HDMI.

2. The converters have no idea what format your ATEM switcher needs and just advertise all possible resolutions that it supports via the HDMI handshake. So cameras and other consumer devices will simply pick the highest supported resolution and transmit that (which in most cases is 1080p60) which when coupled with problem #1 above means it's the wrong resolution that the ATEM doesn't support.